But
with the Zika virus spreading rapidly in Central & South America, the number of Zika infected travelers to
the United States is expected to increase.

Any travelers who are viremic (producing large quantities virus in their blood), and arrive in areas where suitable mosquito vectors are present,
could potentially `seed' the virus to the local mosquito population and start small chains of local transmission.

While Zika virus infection is mild for most people, there are anecdotal reports of increases in Guillain-Barré syndrome in regions where outbreaks have occurred, and mounting concerns that maternal infection during the 1st and 2nd trimester may produce profound microcephalic birth defects.

Given
that Zika is an exotic and unfamiliar disease to most American doctors, late yesterday the CDC issued a LEVEL-2 Travel Advisory and the following HAN Advisory to help doctors identify, treat and report cases.

Summary

In May 2015, the World Health Organization reported the first local
transmission of Zika virus in the Western Hemisphere, with autochthonous
(locally acquired) cases identified in Brazil. As of January 15, 2016,
local transmission had been identified in at least 14 countries or
territories in the Americas, including Puerto Rico (See Pan American
Health Organization [PAHO] link below for countries and territories in
the Americas with Zika virus transmission). Further spread to other
countries in the region is likely.

Local transmission of Zika virus has not been documented in the
continental United States. However, Zika virus infections have been
reported in travelers returning to the United States.

With the recent
outbreaks in the Americas, the number of Zika virus disease cases among
travelers visiting or returning to the United States likely will
increase. These imported cases may result in local spread of the virus
in some areas of the continental United States, meaning these imported
cases may result in human-to-mosquito-to-human spread of the virus.

Zika virus infection should be considered in patients with acute
onset of fever, maculopapular rash, arthralgia or conjunctivitis, who
traveled to areas with ongoing transmission in the two weeks prior to
illness onset. Clinical disease usually is mild. However, during the
current outbreak, Zika virus infections have been confirmed in several
infants with microcephaly and in fetal losses in women infected during
pregnancy. We do not yet understand the full spectrum of outcomes that
might be associated with infection during pregnancy, nor the factors
that might increase risk to the fetus. Additional studies are planned to
learn more about the risks of Zika virus infection during pregnancy.

Healthcare providers are encouraged to report suspected Zika virus
disease cases to their state health department to facilitate diagnosis
and to mitigate the risk of local transmission. State health departments
are requested to report laboratory-confirmed cases to CDC. CDC is
working with states to expand Zika virus laboratory testing capacity,
using existing RT-PCR protocols.

This CDC Health Advisory includes information and recommendations
about Zika virus clinical disease, diagnosis, and prevention, and
provides travel guidance for pregnant women and women who are trying to
become pregnant. Until more is known and out of an abundance of caution,
pregnant women should consider postponing travel to any area where Zika
virus transmission is ongoing. Pregnant women who do travel to these
areas should talk to their doctors or other healthcare providers first
and strictly follow steps to avoid mosquito bites during the trip. Women
trying to become pregnant should consult with their healthcare
providers before traveling to these areas and strictly follow steps to
avoid mosquito bites during the trip.

Background

Zika virus is a mosquito-borne flavivirus transmitted primarily by Aedes aegypti. Aedes albopictus
mosquitoes might also transmit the virus. Outbreaks of Zika virus
disease have been reported previously in Africa, Asia, and islands in
the Pacific.

Clinical DiseaseAbout one in five people infected with Zika virus become
symptomatic. Characteristic clinical findings include acute onset of
fever, maculopapular rash, arthralgia, or conjunctivitis. Clinical
illness usually is mild with symptoms lasting for several days to a
week. Severe disease requiring hospitalization is uncommon and
fatalities are rare. During the current outbreak in Brazil, Zika virus
RNA has been identified in tissues from several infants with
microcephaly and from fetal losses in women infected during pregnancy.
The Brazil Ministry of Health has reported a marked increase in the
number of babies born with microcephaly. However, it is not known how
many of the microcephaly cases are associated with Zika virus infection
and what factors increase risk to the fetus. Guillain-Barré syndrome
also has been reported in patients following suspected Zika virus
infection.

DiagnosisZika virus infection should be considered in patients with acute
onset of fever, maculopapular rash, arthralgia, or conjunctivitis who
recently returned from affected areas. To confirm evidence of Zika virus
infection, RT-PCR should be performed on serum specimens collected
within the first week of illness. Immunoglobulin M and neutralizing
antibody testing should be performed on specimens collected ≥4 days
after onset of illness. Zika virus IgM antibody assays can be positive
due to antibodies against related flaviviruses (e.g., dengue and yellow
fever viruses). Virus-specific neutralization testing provides added
specificity but might not discriminate between cross-reacting antibodies
in people who have been previously infected with or vaccinated against a
related flavivirus.

There is no commercially available test for Zika virus. Zika virus
testing is performed at the CDC Arbovirus Diagnostic Laboratory and a
few state health departments. CDC is working to expand laboratory
diagnostic testing in states, using existing RT-PCR protocols.
Healthcare providers should contact their state or local health
department to facilitate testing.

Treatment

No specific antiviral treatment is available for Zika virus
disease. Treatment is generally supportive and can include rest, fluids,
and use of analgesics and antipyretics. Because of similar geographic
distribution and symptoms, patients with suspected Zika virus infections
also should be evaluated and managed for possible dengue or chikungunya
virus infection. Aspirin and other non-steroidal anti-inflammatory
drugs (NSAIDs) should be avoided until dengue can be ruled out to reduce
the risk of hemorrhage. In particular, pregnant women who have a fever
should be treated with acetaminophen. People infected with Zika,
chikungunya, or dengue virus should be protected from further mosquito
exposure during the first few days of illness to reduce the risk of
local transmission.

Prevention

No vaccine or preventive drug is available. The best way to prevent Zika virus infection is to:

Avoid mosquito bites.

Use air conditioning or window and door screens when indoors.

Wear long sleeves and pants, and use insect repellents when
outdoors. Most repellents, including DEET, can be used on children older
than two months. Pregnant and lactating women can use all Environmental
Protection Agency (EPA)-registered insect repellents, including DEET,
according to the product label.

Recommendations for Health Care Providers and Public Health Practitioners

Zika virus infection should be considered in patients with acute
fever, rash, arthralgia, or conjunctivitis, who traveled to areas with
ongoing transmission in the two weeks prior to onset of illness.

All travelers should take steps to avoid mosquito bites to prevent Zika virus infection and other mosquito-borne diseases.

Until more is known and out of an abundance of caution, pregnant
women should consider postponing travel to any area where Zika virus
transmission is ongoing. Pregnant women who do travel to one of these
areas should talk to their doctors or other healthcare providers first
and strictly follow steps to avoid mosquito bites during the trip. Women
trying to become pregnant should consult with their healthcare
providers before traveling to these areas and strictly follow steps to
avoid mosquito bites during the trip.

Fetuses and infants of women infected with Zika virus during
pregnancy should be evaluated for possible congenital infection and
neurologic abnormalities.

Healthcare providers are encouraged to report suspected Zika virus
disease cases to their state or local health department to facilitate
diagnosis and to mitigate the risk of local transmission.

Health departments should perform surveillance for Zika virus
disease in returning travelers and be aware of the risk of possible
local transmission in areas where Aedes species mosquitoes are active.

State health departments are requested to report laboratory-confirmed Zika virus infections to CDC.

The Centers for Disease Control and Prevention
(CDC) protects people's health and safety by preventing and controlling
diseases and injuries; enhances health decisions by providing credible
information on critical health issues; and promotes healthy living
through strong partnerships with local, national and international
organizations.